The series, which benefited from generally positive reviews and a huge publicity campaign by the network, opened to about 10.5 million viewers Monday (Aug. 29), giving FOX its best summertime Monday numbers since episodes of "Melrose Place" and "Ally McBeal" aired there in September 1998. "Prison Break" helped FOX win the night in all the measures it cares about, including total viewers, adults 18-49 and adults 18-34.

The two-hour premiere (which FOX is counting as two episodes) delivered a 4.6 rating among adults 18-49, tying with the premiere of "So You Think You Can Dance" for the network's best performance of the summer in the demographic. It predictably carried the night among male viewers, but it also did surprisingly well among women, leading the night among women 18-34 and 18-49.

The show also grew in every half-hour, a good sign for any show.

"Prison Break" compares favorably to other recent FOX shows that started before the official opening of the TV season. "The O.C." debuted to about 7.5 million viewers in August 2003, while last year "North Shore," "Quintuplets" and "Method and Red" averaged between 5.9 million and 8.2 million for their premieres, all of which were in June.

Ratings for "Prison Break" will likely drop next week, when the show airs on the Labor Day holiday; FOX is planning to re-air the episode the following night, Tuesday, Sept. 6. The network will also repeat the premiere at 8 p.m. ET Thursday (Sept. 1).